Valve control and reversing mechanism



May 10, 1938. T. STEVENSON ET AL 2,117,109

VALVE CONTROL AND REVERSING MECHANISM Filed July 25, 1955 s Sheets-Sheet1 J m v Q/J 36. v

Y INVENTOR.

fi ma S S E/@1156? BY a #6! 6. [105 54% MM V ATTORNEY y 1938- 'r.STEVENSON ET AL VALVE CONTROL AND REVERSING MECHANISM Filed July 25,1935 3 Sheets-Sheet 2 INVENTOR.

n/\O 3% 4M8 s4 r n mc w y 0, 1938- 'r. STEVENSON ET AL 2,117,109

VALVE CONTROL AND REVERSING MECHANISM Filed July 25, 1935 3 Sheets-Sheet3 IN VENTOR.

ATTORNEY.

Patented May 10, 1 938 UNITED STATES PATENT OFFICE VALVE CONTROL ANDREVERSING Goby, Cleveland, Ohio;

Mary E. Stevenson executrix of said Thomas Stevenson, deceasedApplication July 25, 1935, Serial No. 33,112

Claims.

This invention relates to a valve control and reversing mechanism forlocomotives. It may be used in connection with any standard valvemechanism, such, for example, as that shown in 5 U. S. patent to HardenNo. 505,764. It is to be understood that so-called reversing mechanismshave also the function of cutting off the steam at certain desiredpositions of the main piston.

It is known that manual valve control and reversing mechanisms now incommon use are difiicult to manipulate, dangerous to engine drivers and,in view of the difiiculty of manipulation and the. tendency of the handlever to kick back, likely to be run at inefiicient cut-off positions;while existing power valve control and reverse mechanisms areinefficient as a result of creeping (change in valve position due tofailure to hold the reach rod in adjusted position) and are uncertain inoperation and consequently dangerous to other employees as well asengine drivers. It is the general object of our invention to overcomethe difficulties noted and to do so by the use of simple, safe andsturdy mechanism in keeping with the general character of locomotiveconstruction.

More specifically, objects of our invention are: to provide mechanismwhich neutralizes the reach-rod forces at a point remote from thecontrol lever and absorbs the pounding of the reach rod thus preventingforces transmitted thereby from; moving the reach rod control means; toprovide an eccentric for absorbing such pounding; to distribute theforce of such pounding to opposed surfaces of the eccentric, and toprovide improved manual and power means for controlling the position ofsaid eccentric.

With the foregoing and other objects in view, our invention consists inall the novel features of construction and arrangements of partshereinafter described and illustrated in the accompanying drawings, inwhich Fig. 1 is a vertical sectional view taken through a hand-operateddevice embodying our invention; Fig. 2 is a horizontal sectioncorresponding substantially to the line 22 of Fig. 1; Figs. 3 and 3 makeup a central vertical section through a power operated form of ourinvention; Fig. 4 is a plan view of the device of Fig. 3; Fig. 5 is afragmentary horizon- 50 tal section showing a portion of the valveconstruction and indicating diagrammatically the operating meanstherefor and Fig. 6 is a fragmentary horizontal section through one endof the power cylinder further illustrating the valve mechanism.

Referring first to the hand operated form of our invention, illustratedin Figs. 1 and 2, the numeral I 0 indicates a suitable base havingupwardly extending side members II and I2. The member I2 is providedwith upstanding arms I3 through the upper ends of which is secured anotched arcuate member I4. Journaled in the walls II and I2 is a shaftI5 upon which is nonrotatably mounted an eccentric I6. Also nonrotatablymounted on the shaft I5 is a gear I I which meshes with a sector gear I8journaled on a transverse shaft I9 also carried by the plates I I andI2. Keyed to the shaft I 9 is a hand lever 20 which is provided with anordinary latch mechanism 2I adapted to engage in notches 22 of thenotched arcuate member I4 whereby to cause rotation of the eccentric I6.A disk 23 is keyed or otherwise non-rotatably secured to the shaft i5and frictionally engages a plate 24 from which depends a weight 25. Thespring 26 is provided for causing a predetermined frictional contactpressure between the elements 23 and 24.

Surrounding the eccentric I6 are eccentric followers 27 and 28 which areprovided with arms 29 and 30 respectively terminating in yokes SI and32. The followers 21 and 28 should have a close working fit with theeccentric but should not fit so tightly as to offer substantialresistance to rotation of the eccentric.

The side walls I I and I2 are provided with a transversely extendingfixed shaft 33 and a transversely extending movable shaft 34. Themovable shaft 34 works in slots 35 in walls II and I2. A lever 36 ismounted on the shaft 33 and connected to the yoke 3|. An arm 3! whichmay be regarded as forming part of the lever 36 nonrotatably mounted onthe shaft 33 is pivoted to a link 38 which at its other end is journaledon the sliding shaft 34. A lever 39 is journaled on the shaft 34 whichamounts to a pivotal connection with the link 38, and is pivoted at 40to the arm 30. The lever 39 extends beyond the point 40 and is connectedat 4| to reach rod 42.

It will be clear from the foregoing that in order to manipulate thereach rod 42, the operator may rotate the eccentric I6 by moving thehand lever 20 to a suitable position. The weight 25 will offer asufiicient resistance to rotation of the shaft I5 that the same cannotbecome accidentally displaced. Furthermore, this weight will, by reasonof its inertia, offer a large resistance to sudden motion of theeccentric responsive to pounding of the reach rod 42 at the same timetending to assume a vertical position under the vibration appliedthrough such reach rod. The 55 major force of the rapid motion of thereach rod, however, will be absorbed by the eccentric surface andrelated linkage, the inertia of the eccentric itself and the frictionbetween the eccentric and the straps 21 and 28. A force on the reach rod42 toward the left will cause the straps 28 to place a binding forceagainst the right surface of the eccentric and, by reason of thepossibility of motion of the shaft 34 in the slot 35 and thetransmission through the link 38 of a force to the link 36 and arm 29, abalancing frictional force will be applied to the left surface of theeccentric through the strap 21. The above described forces tending toprevent rotation of the eccentric 16 under the pounding of the reach rodare in effect in all positions of the eccentric, but when the weight isin the position shown in Fig. 1, the eccentric is on dead center andthere is no tendency for the reach rod to cause rotation thereof. It iscontemplated that full forward motion will be secured when the elementsare in the position shown in Fig. 1 and that full reverse motion will besecured when the eccentric is located 180 from this position. It is,however, to be understood that our invention is not limited to such,relation of the reverse gear and the valve mechanism. In addition to.the above'enumerated forces tending to prevent rotation of the cocentricI6 may be mentioned the holding effect of the operating handle 26Working through the sector I8. and the gear I1. Since the reach rodforces are neutralized before reaching the gear sector, the possibilityof hand lever (29) kickback when unlatched is removed. The notches inthe arcuate member 14 serve to indicate the position of steam cut-offand prevent accidental movement of lever 29.

Referring now to Figs. 3 to 6 inclusive, it will be seen that with theexception of the operating lever. 26 and sector gear 18, the abovedescribed mechanism is substantially common to the two forms. The commonelements, therefore, will be given the same numerals as applied to themin the first described form of the invention and further description oftheir construction, relations and operations will be omitted.

The gear 11 is operated, in this form, by means. of a rack bar 43meshing therewith (preferably with some play) and connected as indicatedat 44 and 45 to pistons 46 and 41 respectively workingin cylinders 48and 49. At the ends of the cylinders 48 and 49 are valve mechanisms 59and 5L which are adapted to admit a suitable fluid, preferablycompressed air, for moving the pistons predetermined distances in thecylinders 48 and, 49. Inasmuch as the two valve mechanisms are ofsubstantially identical construction, the details. of one only of themare shown. By reference. to- Fig. 6 it will be seen that the cylinder-49 is provided with a flange 52 to which is secured a flange 53 of thevalve cylinder 59. Flange 53 is integral with the body portion of thevalve which latter has a cylindrical bore extending transversely of thebore of the cylinder 48 and receiving inner and outer sleeve valves 54and 55 respeotively. The fluid inlet 56 communicates through a suitableend cap 51 to the interior of the valve. 50 and to the interior of thesleeve valves. At the other end of the valve body is a second end cap 58through which the operating extensions '59 and 60 of said sleeve valvespass. The innermost sleeve 54 has a passage through its operating.extension 59 for allowing exhausting ofv the operating fluid. Theextension 59 at its junction with sleeve 54 is provided with a valveseat 61 adapted to cooperate with a movable valve element 62 carried bya piston 63 working within the inner valve 54. A spring 64 is providedfor normally urging the valve elements 62 to open position. The valvebody is provided with a passage 65 for admission of operating fluid fromthe inlet 56 to the interior of the cylinder 43 and is provided with asmaller passage 66 (always open) providing for the escape of the exhaustoperating fluid when the valve element 62 is in open position.

By reference to Fig. 5 the relation of the ports 55 and. the ports 61and 68 will be readily apparent. The outer sleeve valves 55 areconnected to suitable operating arms 69 and 10 which in turn areconnected by links 1| and 12 to the arms 29 and 30. The inner sleeves 54are connected to suitable arms 13 and 14 which in turn are connectedtogether by rod 15 which is controlled by a hand lever 16 operating witha suitable arcuate notched member 11 and having any suitable latch 18.Assuming that the valve elements are in the position shown in Fig. 5,and it is desired to admit operating fluid to the cylinder 49 whereby tomove the rack 43 a predetermined distance toward the right, theoperating lever 16.. will be moved clockwise a predetermined desireddistance which will result in rotating the elements 13 and 14 acorresponding distance clockwise and thereby bringing the slot 68 intoregistry with the slot 61, at the same time moving the slot 68' acorresponding distance further out of registry with the slot 61. Thecompressed air valves 93 and 90 may then be manipulated to admitcompressed air to the cylinder 49. The pistons and the rack bar willthen move toward the right which will result in a counterclockwiserotation of the gear 11 and a consequent motion of the arm 30 toward theright, thus manipulating the reach rod 42 and at the same time operatingthe link 11, to rotate the arm 69 clockwise to bring the outer sleeveValve to a cut-off position, thus limiting the motion of the pistons toan amount proportionate to the rotation of the operating rod 16.

It will. be noted that rotation of the gear 11 and the shaft 15 isnormally opposed by a brake 19 operating in a groove 86 formed in abrake drum 8| non rotatably carried by the shaft l5. However, when, theoperating fluid is admitted frointhe supply line 82 through the valve83, it will. pass through a pipe 84 to a cylinder 85 where it will forcea slightly loose-fitting piston 86 tothe right against the action of aspring 81 thereby operating against the action of a spring 81 andoperating the brake arm to release the brake. As soon as the valve 83 ismoved to closed position, the spring 81 will restore the brake tooperative position. The supply of operating fluid passes also throughthe pipe 89 toa selector valve 99 which may be an ordinary three-wayvalve adapted to open a selected one of the pipes 91 and 92 whileclosing the other. The supply pipes 91 and-92 communicate to theinterior of the valves 56and 51, as clearly indicated.

From the foregoing, it will be apparent that when itis desired tooperate the reach rod 42, the hand lever 16 may be moved a distancecorresponding to that to which it is desired to move the reach rod,after which the valve may be set by means of an operating handle 93working through a link 94 to admit the operating fluid'to oneofthecylinders 4B and 49 depending upon thedirection in'which it isdesired to rotate the gear I1 and that the operating fluid supply maythen be made active by opening the normally spring closed valve 83.

While we have illustrated and described the present preferred embodimentof our invention, we wish it to be understood that it may be embodied inother structures and that we are limited only in accordance with theappended claims and the prior art.

Having thus described our invention, what we claim is:

1. In combination, in a reversing mechanism for locomotives, a base, alever adapted to be pivoted to a reach rod, a second lever pivoted tosaid base, an eccentric journaled on said base, a pair of eccentricfollowers associated with said eccentric and pivotally connected, onopposite sides thereof, one to each of said levers, a link connected tosaid second lever intermediate its two said pivot points and connectedto said first lever by a pivot connection slidably mounted on said base.

2. In combination, in a reversing mechanism for locomotives, a reachrod, a base, an eccentric journaled on said base, eccentric followersoperated by said eccentric, means cooperating with said eccentric andsaid eccentric followers to form a parallelogram linkage connecting saideccentric in operative relation to said reach rod and means forcontrolling the position of said eccentric, said last means including acontrol lever for adjusting the position of said eccentric and means inaddition to said control lever for resisting change of position of saideccentric.

3. In combination, in a reversing mechanism for locomotives, a reachrod, a base, an eccentric journaled on said base, eccentric followersoperated by said eccentric, means. cooperating with said eccentric andsaid eccentric followers to form a parallelogram linkage connecting saideccentric in operative relation to said reach rod and means forcontrolling the position of said eccentric, said last means including acontrol lever for adjusting the position of said eccentric and means inaddition to said control lever for offering a resistance to change ofposition of said eccentric, said last means including a weight wherebyto offer a resistance inversely proportional to the duration of theapplied force tending to produce motion of said eccentric.

4. In combination, in a reversing mechanism for locomotives, a base, alever slidably pivoted to said base at one point and adapted to bepivoted to a reach rod at a spaced point, an eccentric journaled on saidbase and having an eccentric follower associated therewith and pivotedto said lever intermediate said points,a second lever,positioned on theopposite side of said eccentric and pivoted to said base, a link pivotedto said first lever adjacent said sliding pivot point and to said secondlever at a point spaced from its pivot connection to the base, a secondeccentric follower operated by said eccentric and pivotally connected tosaid second lever, and means for adjusting the position of saideccentric.

5. In combination, in a reversing mechanism for locomotives, a base, alever slidably pivoted to said base at one point and adapted to bepivoted to a reach rod at a spaced point, an eccentric journaled on saidbase and having an eccentric follower associated therewith and pivotedto said lever intermediate said points, a second lever,

csitioned on the opposite side of said eccentric and pivoted to saidbase, a link pivoted to said first lever adjacent said sliding pivotpoint and to said second lever at a point spaced from its pivotconnection to the base, a second eccentric follower operated by saideccentric and pivotally connected to said second lever, and means foradjusting the position of said eccentric, said last means including apinion mounted for rotation with said eccentric, gear means meshing withsaid pinion and means for operating said gear means a distancesufficient to rotate said pinion through substantially 180 of arc.

6. In combination, in a reversing mechanism for locomotives, a base, alever slidably pivoted to said base at one point and adapted to bepivoted to a reach rod at a spaced point, an eccentric journaled on saidbase and having an eccentric follower associated therewith and pivotedto said lever intermediate said points, a second lever, positioned onthe opposite side of said eccentric and pivoted to said base, a linkpivoted to said first lever adjacent said sliding pivot point and tosaid second lever at a point spaced from its pivot connection to thebase, a second eccentric follower operated by said eccentric andpivotally connected to said second lever, and means for adjusting theposition of said eccentric, said last means including a pinion mountedfor rotation with said eccentric, gear means meshing with said pinionand means for operating said gear means a distance sufficient to rotatesaid pinion through substantially 180 of arc, and separate means foropposing motion of said eccentric as a result of forces transmittedthereto through said eccentric followers.

7. In combination, in a reversing mechanism for locomotives, a base, alever movably carried by said base and adapted to control a reach rod, asecond lever pivoted to said base, a link pivoted to both said levers,an eccentric mounted on said base, means for rotating and controllingthe position of said eccentric, and means including eccentric followerspivoted to said levers for transmitting motion of said eccentric to saidlever and for transmitting forces applied to said lever partly to oneportion of said eccentric and partly to an opposed portion thereof.

, 8. In combination, in a reversing mechanism for locomotives, a base, alever movably carried by said base and adapted to control a reach rod, asecond lever pivoted to said base, a link pivoted to both said levers,an eccentric mounted on said base, means for rotating and controllingthe position of said eccentric, means including eccentric followerspivoted to said levers for transmitting motion of said eccentric to saidlever and for transmitting forces applied to said lever partly to oneportion of said eccentric and partly to an opposed portion thereof, andfriction means for opposing motion of said eccentric responsive topounding of the reach rod.

9. In combination, in a reversing mechanism for locomotives, a base, alever movably carried by said base and adapted to control a reach rod, asecond lever pivoted to said base, a link pivoted to both said levers,an eccentric mounted on said base, means for rotating and controllingthe position of said eccentric, and means including eccentric followerspivoted to said levers for transmitting motion of said eccentric to saidlever and for transmitting forces applied to said lever partly to oneportion of said eccentric and partly to an opposed portion thereof, saidfirst means including a pinion mounted for rotation with said eccentric,a rack movable tangentially of said pinion and meshing therewith, andfluid pressure operated means for moving said rack predeterminedselected distances.

iii

10. In combination, in a reversing mechanism for locomotives, a base, alever movably carried by said base and adapted to control a reach rod,2; second lever pivoted to said base, a link pivoted to both saidlevers, an eccentric mounted on said base, means for rotating andcontrollingthe position of said eccentric, and means including eccentricfollowers pivoted to said levers for transmitting motion of saideccentric to said lever and for transmitting forces applied to saidlever partly to one portion of said eccentric and partly to an opposedportion thereof, said first means including a pinion mounted forrotation with said eccentric, a rack movable tangentially of said pinionand meshing therewith, fluid pressure operated means for moving' saidrack predetermined selected distances, friction means normally oposingrotation of said eccentric and means automatically operableconcomitantly with application of fluid pressure to said fiuidpressureoperat'ed means for releasing said friction means.

THOMAS STEVENSON. CLIFFORD S. GOBY.

